White-lead corroding-pit



UNITED STATES PATENT OFFICE.

WILLIAM HENRY \VETHERILL, OF'PHILADELPHIA, PENNSYLVANIA.

WHITE-LEAD. CORRODING-PIT.

SPECIFICATION forming part of Letters Patent No. 478,488, dated July 5, 1892.

Application filed March 1, 1892. $erial No. 423,385. (No model.)

To all whom it may concern:

Be it known that I, WILLIAM HENRY WETH- ERILL, of Philadelphia,in the county of Philadrawings, forming a part thereof, in which- Figure 1 is a vertical transverse section of my improved white-lead corroding-pit, taken on the line so a: in Fig. 2; and Fig. 2 is a horizontal section taken on line y y in Fig. 1.

Similar letters of reference indicate corresponding parts in both views.

My invention is an improvement in that class of structures which are used for effecting the corrosion of lead, and to this end are provided with side openings and a central vertical tube or chimney to facilitate the circulation of air, upon which the rapidity of the corrosion in a great measure depends.

In carrying out my invention I dig a pit A in the earth and provide a suitable floor B and line the pit with walls 0 of masonry. As the walls are carried up blocks of wood are laid with the masonry, which are afterward driven out, leaving the ventilating-holes a a, and with these holes I connect pipes 1), lead-. ing to the surface of the ground, one pipe to each set of ventilating-holes a a. In the center of the pit I erect a perforated ventilating-shaft D, which extends above the surface of the ground and above the top of the superstructure E. The said superstructure is erected upon the walls 0.

The lead is placed in the pit in layers, alternating with layers of wet fibrous material in the usual manner. As the corrosion proceeds heat is generated and a column of heated air is carried up the ventilating-shaft D, thus causing fresh air to enter through the pipes b, creating a rapid circulation through the layers of fibrous material between the layers of lead, thus hastening the process.

A pit is superior to the Wooden corrodiughouse usually built above ground in point of strength, durability, and economy, as well as the conservation of heat. The tubes 1) are necessary parts or features of such pit, since they enable air to enter freely and prevent obstruction of the openings a, which would otherwise occur.

Having thus described my invention, I claim as new and desire to secure by Letters Patent- The combination, with the pit-walls O, having the ventilating-holes a a, of a series of pipes 19, open at the top, embedded in the surrounding earth, arranged around the walls exteriorly, and leading upward from said holes, as shown and described, for the purpose specified. A

WILLIAM HENRY WETIIERILL.

Witnesses:

O. H. WATSON, J. A. DOWDE. 

